Road section vehicle group dissipation method based on real-time vehicle speed regulation

Abstract

The application relates to a road section vehicle group dissolving method based on real-time vehicle speed regulation, which comprises the following steps: S1, acquiring real-time traffic information of a road section; S2, when the headway between a host vehicle and a front vehicle in the same lane is less than a safe following headway and the headways between the host vehicle and front vehicles in adjacent lanes are both less than a safe lane-changing headway, the front vehicle in the same lane and the front vehicles in the adjacent lanes form a vehicle group; S3, judging the risks of vehicles in the vehicle group, and the vehicle with the maximum risk value R being the risk source of the vehicle group; S4, regulating the vehicle speed of the risk source vehicle of the vehicle group; and S5, when the host vehicle satisfies the condition that the headway with the front vehicle in the same lane is greater than or the headway with the front vehicle in the adjacent lane is greater than, the original vehicle group is dissolved. The application dissolves the vehicle group and reduces the driving risk of the road section by regulating the real-time vehicle speed of the risk source vehicle.

Description

Technical Field

[0001] This invention relates to the field of traffic safety management and collaborative control, and more specifically, to a method for mitigating traffic groups on road sections based on real-time vehicle speed control. Background Technology

[0002] With rapid economic and transportation development, road construction standards are constantly improving, and the number of vehicles is continuously increasing, making traffic efficiency and safety issues increasingly serious. On highways and urban expressways, high vehicle speeds easily lead to rear-end collisions. Furthermore, close following is common in highway transportation; when vehicles move in groups, sudden braking within the group often results in chain-reaction rear-end collisions and other serious traffic accidents. Therefore, real-time and accurate identification and timely management of traffic risks in road sections are of great significance.

[0003] In road traffic, the interactions between vehicles have a significant impact on traffic flow stability and traffic safety. Especially under high-density traffic conditions, the relationships between vehicles become more complex, and reducing the instability caused by these interactions is a crucial issue in traffic management and safety research. Currently, methods for identifying and controlling road segment driving risks mainly focus on identifying interactions between single vehicles; however, multi-vehicle interactions are more likely to cause large-scale traffic congestion and lead to serious traffic accidents. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a method for resolving traffic clusters on road sections based on real-time vehicle speed control. The method defines a group of vehicles with strong interaction relationships within a road section that affects the normal lane changing of following vehicles as a vehicle cluster. Then, it identifies risk source vehicles within the vehicle cluster and resolves the vehicle cluster by real-time speed control of the risk source vehicles, thereby reducing the driving risk of the road section.

[0005] The technical solution adopted by this invention to solve its technical problem is: to construct a method for resolving traffic group issues on road sections based on real-time vehicle speed control, comprising the following steps:

[0006] S1. Obtain real-time traffic information for the road segment;

[0007] S2. When the headway between the main vehicle and the vehicle in front in the same lane is less than the headway of the safe following vehicle. Furthermore, the headway between the main vehicle and the vehicle in front in the adjacent lane is less than the headway of a vehicle changing lanes safely. At that time, the vehicle in front of the main vehicle in the same lane and the vehicle in front of the vehicle in the adjacent lane form a group of vehicles;

[0008] S3. Determine the risk of each vehicle in the vehicle group. The vehicle with the highest risk value R is the risk source of the vehicle group.

[0009] S4. Adjust the speed of vehicles at risk sources in the vehicle cluster;

[0010] S5. When the distance between the front of the vehicle and the vehicle in front in the same lane is greater than... Or the headway between the main vehicle and the vehicle in front in the adjacent lane is greater than At that time, the original car group was dissolved.

[0011] According to the above scheme, in step S1, the real-time traffic information of the road segment includes: the lateral speed v of vehicles within the road segment. x Longitudinal velocity v y lateral acceleration a x Longitudinal acceleration a y Model V T Lane L n , and the distance H between the front and rear of the vehicle in front, calculate the headway between the front vehicle in the same lane and the headway between the front vehicles in adjacent lanes.

[0012] According to the above scheme, the lateral velocity v x The longitudinal velocity v is the velocity perpendicular to the lane line direction. y The lateral acceleration a is the velocity along the lane line direction. x The longitudinal acceleration a is the acceleration perpendicular to the lane line direction. y This refers to the acceleration along the lane line.

[0013] According to the above scheme, in step S2, when the headway between the main vehicle and the vehicle in front in the same lane is less than the headway of the safe following vehicle. When it is determined that the main vehicle intends to change lanes, and the headway between the main vehicle and the vehicle in front in the adjacent lane is less than the safe headway for lane changing,... If it is determined that the main vehicle does not meet the conditions for a safe lane change, then the main vehicle in the same lane and the vehicle in front in the adjacent lane constitute a traffic group.

[0014] According to the above scheme, in step S3, the weights of each evaluation index factor are assigned for different road scenarios, ∑P i =1.

[0015] According to the above scheme, in step S3, the lateral speed v of the vehicle is selected. x Longitudinal velocity v y lateral acceleration a x Longitudinal acceleration a y Model V T P is an indicator for identifying risk sources. i This indicates the weight of each evaluation indicator factor, and calculates the risk value of each vehicle within the vehicle group.

[0016] According to the above scheme, in step S4, the vehicle speed of the vehicles at risk of the vehicle cluster is controlled using an objective function, which is v = minv T Target vehicle speed v T The constraints are:

[0017]

[0018] In the above formula:

[0019] v d Indicates the speed of vehicles following in the same lane as the vehicle from the risk source.

[0020] v l This indicates the vehicle ahead of the vehicle in the same lane as the source of the risk.

[0021] v H1 and v H2 Indicates the minimum and maximum speed limits for the lane;

[0022] H represents the distance between the front of the vehicle at risk and the vehicle in front in the same lane;

[0023] t safe Indicates the minimum safe shift time;

[0024] Δt represents the time of the speed regulation process;

[0025] x l (Δt) represents the position of the vehicle ahead of the vehicle in the same lane as the risk source vehicle when speed control is completed;

[0026] x i (Δt) represents the position of the vehicle at risk when speed control is completed;

[0027] s safe This indicates the minimum safe distance.

[0028] According to the above scheme, in step S4, v T ≥max(v d v H1 The minimum speed constraint is defined as follows: the controlled speed must not be less than the maximum of the minimum speed limit for this lane and the speed of the vehicle behind; v T ≤min(v l v H2 The maximum speed constraint is that the controlled speed shall not exceed the minimum of the maximum speed limit of this lane and the speed of the vehicle in front. To ensure safe shifting time, the speed adjustment completion time must not be less than the safe shifting time; x l (Δt)-x i (Δt)≥s safe To avoid collisions, the distance between the front of the vehicle at risk and the vehicle in front in the same lane must not be less than the minimum safe distance when speed control is completed.

[0029] According to the above scheme, in step S4, if the target vehicle speed v T If no feasible solution is found, speed control is not performed, and a lane change operation is executed. If a lane change is not possible, there is a traffic cluster in front of the risky vehicle, and steps S3 to S4 are repeated.

[0030] According to the above scheme, in step S5, if the headway between the main vehicle and the vehicle in front in the same lane is greater than the minimum safe following distance or the lane-changing conditions are met, the original vehicle group will be eliminated.

[0031] The method for mitigating traffic congestion on road sections based on real-time vehicle speed control, as described in this invention, has the following beneficial effects:

[0032] This invention proposes a method for determining multi-vehicle interaction relationships. Vehicle groups with strong interaction relationships within a road segment that affect the normal lane changing of following vehicles are defined as vehicle clusters. By identifying risk source vehicles within a vehicle cluster and adjusting the speed of these risk source vehicles in real time, vehicle clusters can be resolved, thereby reducing the driving risk of the road segment. Through real-time speed control, the driving risks of vehicle clusters on a road segment can be accurately identified and managed in a timely manner, thereby reducing the occurrence of major traffic accidents. It can effectively reduce the instability caused by complex interactions between vehicles under high-density traffic flow conditions, improving road segment traffic safety. By resolving vehicle clusters, it can help reduce the occurrence of large-scale traffic congestion, thereby improving the operational efficiency of the road segment. Attached Figure Description

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments. In the accompanying drawings:

[0034] Figure 1 This is a flowchart of the method for resolving traffic congestion on road sections based on real-time vehicle speed control according to the present invention;

[0035] Figure 2 This is a schematic diagram illustrating the interaction between the vehicle SV and surrounding vehicles according to the present invention;

[0036] Figure 3 This is a schematic diagram illustrating the interaction between the vehicle (PV) and the vehicle in front of it according to the present invention. Detailed Implementation

[0037] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0038] like Figure 1 As shown, the method for mitigating traffic congestion on road sections based on real-time vehicle speed control of the present invention includes the following steps:

[0039] S1. Obtain real-time traffic information for the road segment; real-time traffic information for the road segment includes: the lateral speed v of vehicles within the road segment. x Longitudinal velocity v y lateral acceleration a x Longitudinal acceleration a y Model V T Lane L n , and the distance H between the front and rear of the vehicle in front, calculate the headway between the front vehicle in the same lane and the headway between the front vehicles in adjacent lanes.

[0040] Lateral velocity v x The velocity perpendicular to the lane line, the longitudinal velocity v y Let a be the velocity along the lane line and the lateral acceleration be a. x The acceleration is perpendicular to the lane line, and the longitudinal acceleration is a. y This refers to the acceleration along the lane line.

[0041] S2. When the headway between the main vehicle and the vehicle in front in the same lane is less than the headway of the safe following vehicle. Furthermore, the headway between the main vehicle and the vehicle in front in the adjacent lane is less than the headway of a vehicle changing lanes safely. At that time, the vehicle in front of the main vehicle in the same lane and the vehicle in front of the vehicle in the adjacent lane form a group of vehicles;

[0042] When the headway between the main vehicle and the vehicle in front in the same lane is less than the headway of the safe following vehicle. When it is determined that the main vehicle intends to change lanes, and the headway between the main vehicle and the vehicle in front in the adjacent lane is less than the safe headway for lane changing,... If it is determined that the main vehicle does not meet the conditions for a safe lane change, then the main vehicle in the same lane and the vehicle in front in the adjacent lane constitute a traffic group.

[0043] S3. Assess the risk of each vehicle within the vehicle cluster. The vehicle with the highest risk value R is identified as the risk source of the cluster. Select the vehicle's lateral velocity v. x Longitudinal velocity v y lateral acceleration a x Longitudinal acceleration a y Model V T P is an indicator for identifying risk sources. i This indicates the weight of each evaluation indicator factor, and calculates the risk value of each vehicle within the vehicle group. Assigning weights to various evaluation index factors for different road scenarios, ∑P i =1.

[0044] S4. Speed ​​control of vehicles at risk sources within a vehicle cluster; The objective function for speed control of vehicles at risk sources within a vehicle cluster is v = minv. T Target vehicle speed v T The constraints are:

[0045]

[0046] In the above formula:

[0047] v d Indicates the speed of vehicles following in the same lane as the vehicle from the risk source.

[0048] v l This indicates the vehicle ahead of the vehicle in the same lane as the source of the risk.

[0049] v H1and v H2 Indicates the minimum and maximum speed limits for the lane;

[0050] H represents the distance between the front of the vehicle at risk and the vehicle in front in the same lane;

[0051] t safe Indicates the minimum safe shift time;

[0052] Δt represents the time of the speed regulation process;

[0053] x l (Δt) represents the position of the vehicle ahead of the vehicle in the same lane as the risk source vehicle when speed control is completed;

[0054] x i (Δt) represents the position of the vehicle at risk when speed control is completed;

[0055] s safe This indicates the minimum safe distance.

[0056] v T ≥max(v d v H1 The minimum speed constraint is defined as follows: the controlled speed must not be less than the maximum of the minimum speed limit for this lane and the speed of the vehicle behind; v T ≤min(v l v H2 The maximum speed constraint is that the controlled speed shall not exceed the minimum of the maximum speed limit of this lane and the speed of the vehicle in front. To ensure safe shifting time, the speed adjustment completion time must not be less than the safe shifting time; x l (Δt)-x i (Δt)≥s safe To avoid collisions, the distance between the front of the vehicle at risk and the vehicle in front in the same lane must not be less than the minimum safe distance when speed control is completed.

[0057] If the target vehicle speed is v T If no feasible solution is found, speed control is not performed, and a lane change operation is executed. If a lane change is not possible, there is a traffic cluster in front of the risky vehicle, and steps S3 to S4 are repeated.

[0058] S5. When the distance between the front of the vehicle and the vehicle in front in the same lane is greater than... Or the headway between the main vehicle and the vehicle in front in the adjacent lane is greater than When the time distance between the lead vehicle and the vehicle in front in the same lane is greater than the minimum safe following distance or the conditions for changing lanes are met, the original vehicle group dissipates.

[0059] Example

[0060] Taking urban expressways as an example, such as Figure 2-3 The real-time interaction relationships between vehicles on the road segment are shown.， Iterate through the vehicle's SV, PV, and PV at this moment. L PV R lateral velocity v x Longitudinal velocity v y lateral acceleration a x Longitudinal acceleration a y The headway TH between each vehicle can be calculated from the distance between the front ends of each vehicle. SV，PV =5s

[0061] Set safe following distance For 5 seconds, safe lane change headway It takes 3.5 seconds. At this time, TH SV，PV At 5 seconds, the vehicle SV indicates an intention to change lanes, but For 1.8s, The time is 1.4s, which does not meet the conditions for a safe lane change. Therefore, the vehicle's PV and PV are both... L PV R They form a group of vehicles.

[0062] right The values ​​are assigned to 0.2, 0.1, 0.2, 0.3, and 0.2 respectively. The vehicle PV has the highest risk value R, which means that the vehicle PV is the risk source of the vehicle group.

[0063] The maximum speed limit for the lane where the vehicle (PV) is located is set to 70 km / h, with no minimum speed limit and a minimum safe shift time t. safe The minimum safe distance is 1.5s. safe For a distance of 5m, the longitudinal velocity v of the vehicle's FV is... y For 68km / h, the distance between the front and rear of the vehicle is H nf It is 39.6m.

[0064] Solve for the target vehicle speed v of vehicle n according to the following constraints. T

[0065]

[0066] The solution shows that after 2.4 seconds, vehicle n reaches the target speed of 64 km / h, and the original vehicle cluster is eliminated.

[0067] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A method for regulating a vehicle group on a road section based on real-time vehicle speed, characterized in that, The method comprises the following steps: S1, acquiring real-time traffic information of a road section; S2. When the headway between the main vehicle and the vehicle in front in the same lane is less than the headway of the safe following vehicle. Furthermore, the headway between the main vehicle and the vehicle in front in the adjacent lane is less than the headway of a vehicle changing lanes safely. At that time, the vehicle in front of the main vehicle in the same lane and the vehicle in front of the vehicle in the adjacent lane form a group of vehicles; S3, judging risks of each vehicle in the vehicle group, and taking a vehicle with the maximum risk value R as a risk source of the vehicle group; S4, performing speed control on the vehicle with the maximum risk value R; S5, when the host vehicle meets the headway distance with the front vehicle in the same lane is greater than or the headway distance of the host vehicle with the front vehicle in the adjacent lane is greater than , the original vehicle group is dissolved; In the step S3, the evaluation index factor weight values are assigned to different road scenes, ; The step S3 selects the vehicle lateral speed , longitudinal speed , lateral acceleration , longitudinal acceleration , vehicle type V T as the risk source determination index, represents the weight of each evaluation index factor, and calculates the risk value of each vehicle in the vehicle group ; In the step S4, the target function is used to control the speed of the risk source vehicle in the vehicle group, and the target function is v = minv T , and the target speed v T is constrained by the following conditions: In the above formula: Vr represents the speed of the risk source vehicle; v l represents a risk source vehicle in the same lane as the preceding vehicle; and denotes the lowest and highest speed limit of the lane; represents the headway of the risk source vehicle from the front vehicle in the same lane; t safe denotes the minimum safe shift time; time representing the speed regulation process; represents the position of the risk source vehicle relative to the front vehicle in the same lane when the speed regulation is completed; represents the position of the risk source vehicle at the time of completion of speed regulation; represents the minimum safety distance.

2. The method of claim 1, wherein the method is based on real-time vehicle speed regulation. The step S1, the road section real-time traffic information includes: the vehicle transverse speed in the road section , the longitudinal speed , the transverse acceleration , the longitudinal acceleration , the vehicle type V T , the lane , and the headway with the front vehicle , the headway with the front vehicle in the same lane and the headway with the front vehicle in the adjacent lane are calculated.

3. The method of claim 2, wherein the method further comprises: the lateral velocity is the velocity perpendicular to the lane line direction, the longitudinal velocity is the velocity along the lane line direction, the lateral acceleration is the acceleration perpendicular to the lane line direction, the longitudinal acceleration is the acceleration along the lane line direction.

4. The method of claim 1, wherein the method further comprises: In the step S2, when the headway between the host vehicle and the front vehicle in the same lane is less than the safe following headway , it is determined that the host vehicle has a lane-changing intention, and when the headways between the host vehicle and the front vehicles in the adjacent lanes are both less than the safe lane-changing headway , it is determined that the host vehicle does not satisfy the safe lane-changing condition, and the front vehicles in the same lane and the adjacent lanes of the host vehicle form a vehicle group.

5. The method of claim 1, wherein, In the step S4, if the target vehicle speed v T If there is no feasible solution, no speed control is performed, the lane changing operation is executed, and if the lane changing cannot be performed, there is a vehicle group in front of the risk vehicle, and the steps S3 to S4 are repeated.

6. The method of claim 1, wherein, In the step S5, if the headway between the host vehicle and the front vehicle in the same lane is greater than the minimum safe following distance or the lane changing condition is met, the original vehicle group is dissolved.

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